The increasing popularity of handheld and other types of portable devices has created new opportunities and challenges for the creators and distributors of media content for playback on those devices, as well as for the designers and manufacturers of the devices. Many portable devices are capable of playing back a broad range of media content types and formats including those often associated with high-quality, wide bandwidth and wide dynamic range audio content for HDTV, Blu-ray or DVD. Portable devices may be used to play back this type of audio content either on their own internal acoustic transducers or on external transducers such as headphones; however, they generally cannot reproduce this content with consistent loudness and intelligibility across varying media format and content types.